The January transfer window continues to leave fans drunk on the thought of who will be the next saviour to walk through the door at their club.

After a relatively low-key opening, things have heated up in the second week of January, not least thanks to Bournemouth and Newcastle both splashing out in excess of £17million each, on two players apiece.

There's plenty more to the Bundesliga than just Bayern Munich and those players being linked with the world elite - naming names, Leroy Sane, Mats Hummels and Pierre-Emerick Aubameyang. In fact, it's a veritable gold mine.

Here are five under-the-radar players to watch, limited to one player per team:

Yunus Malli (Mainz)

Position: Winger/No.10

Age: 23

Hitman: Malli has played for Turkey at senior level - but Germany are still keen (Photo: Getty)

After their Euro 2000 debacle, the German Football Federation (DFB) sought to ensure that it would never happen again. Long story short, scouting links were set up, more young players were seen and an increasing number of players with dual-nationality - who would likely have been lost previously - arrived on Die Mannschaft's radar. Some flourished from the youth teams through to the seniors: World Cup winners Lukas Podolski, Sami Khedira and Mesut Ozil are just three examples.

Mainz attacking midfielder Yunus Malli looked set to be the latest. Having represented Germany from under-16 to under-21 level - winning the UEFA U17 European Championship alongside Mario Götze and Marc-Andre ter Stegen in 2009 - Malli was being lined up DFB sporting director Hansi Flick for senior honours in October. In November however, he made his debut for Turkey, having opted for the country of his parents. Now he is eyeing a place in Fatih Terim's Euro 2016 squad.

Breaking out: Malli has notched a third of Mainz's goals so far (Photo: Alexander Hassenstein)

Comparisons with Arsenal star Ozil extend further than just their heritage. The 23-year-old attacking midfielder has made the Coface Arena his own this term after breaking through last season.

Having seen star men Shinji Okazaki and Johannes Geis depart in the summer, Malli is now the creative fulcrum for Martin Schmidt's side, the technical leader behind the much-vaunted Japanese forward Yoshinori Muto . Between them, the pair have 15 of Mainz's 23 league goals this term: Malli has eight, his best ever seasonal total.

That added clinical edge has ensured he is now a far greater threat in the final third. Always a clever passer (with either foot) who interprets space between the lines intelligently, he's added an extra dimension to his game. After key departures last summer, he's stepped up to the plate and delivered. Mainz have a recent history of signing and selling intelligently, and Malli could be the next on the move.

Granit Xhaka (Borussia Monchengladbach)

Position: Centre midfield

Age: 23

Growth: Xhaka is now the technical leader for Gladbach (Photo: Dean Mouhtaropoulos)

Having seemingly been around forever but still only 23, Swiss playmaker Granit Xhaka is now the heartbeat of a Borussia side looking to bring the good times back to Gladbach.

Xhaka arrived at Borussia-Park in 2012, arriving for £6.3million from Swiss side Basel, having been one of two shooting stars at St Jakob’s Park. While Xherdan Shaqiri moved to Europe’s elite - Bayern Munich and Inter Milan, seeing his reputation grow immeasurably - Xhaka took a more modest route as he looked to hone his game; his talent has never been in doubt, however his inconsistencies needed ironing out. Mostly that has happened, occasional hot-headedness aside.

Now, six months after his peer's career has taken a slight downward step, Xhaka’s star continues to rise. Handed the captain’s armband by new manager Andre Schubert, Xhaka is now Die Fohlen’s creative hub, sculpting play from the heart of midfield with his immaculate left foot.

Up for the challenge: Xhaka gets to grips with Juventus star Paul Pogba (Photo: Valerio Pennicino)

Technically gifted, he reads the game well and is robust enough to do the nasty work as well; in many ways he’s similar to Spurs’ Dele Alli, capable of throwing himself into a block on the edge of his own box, before popping up 10 seconds later looking to fire a shot at goal. His former Swiss coach Ottmar Hitzfeld once labelled him “young Schweinsteiger”.

After a dismal start to the season, Gladbach are once again challenging for a top four spot in Germany. Xhaka has been a key reason why, flourishing under the added responsibility Schubert has thrust upon him. However, his ascent in the last 12 months means Gladbach are unlikely to be able to keep hold of him much longer. Bayern Munich have been mentioned as a potential destination, as have Arsenal.

Jonas Hector (FC Koln)

Position: Left-back

Age: 25

Progress: Hector has established himself in the top flight with Koln (Photo: Mika Volkmann/Bongarts/Getty)

One of the intriguing things about Germany's ascent at international level in recent years has been the absence of genuine full-backs at Jogi Low's disposal. Phillip Lahm captained them to the 2014 World Cup but was often used in midfield (until later in the competition), while Schalke centre-back Benedikt Howedes played throughout at left-back. Ahead of Euro 2016, Koln defender Jonas Hector may have offered a solution.

Now 25, Hector is something of a late developer. At 19, he was still playing for SV Auersmacher, then in the fifth tier. At 24, as Germany were emerging victorious in Brazil, he still hadn't made his Bundesliga debut.

In the ensuing 18 months however, the powerful left-back has made 10 appearances for his country, having originally been called up by Low after just 11 top-flight matches. Since then, he has gone from strength-to-strength with Koln, featuring in 50 of 51 Bundesliga matches since their promotion. His stamina and lack of injury problems are just another reason why Low is such a fan.

However, this would mean nothing without quality, something Hector has both defensively and in attack. Few modern full-backs are defensively as sound on crosses coming from the opposite flank, and he's strong in one vs one situations with opposing wingers also. Offensively, he may not be David Alaba, but he's an effective option on the overlap and works well in combination play.

Sven Bender (Borussia Dortmund)

Position: Centre midfield

Age: 26

Reduced role: Bender has been largely used in defence this term (Photo: Alexandre Simoes/Borussia Dortmund/Getty)

His maturity into a midfield anchor played a big role in Dortmund's progress from Bundesliga hopefuls to champions under Jurgen Klopp, but Sven Bender is no longer an assured starter at the Westfalenstadion.

Tough in the tackle and diligent in his defensive duties, he has long offered a strong base in front of the back four. However, fitness concerns have often reared their head and continue to do so, meaning he's no longer first-choice in his preferred role.

The 26-year-old is into his seventh year with Dortmund, but it could well prove his last. Under new Dortmund chief Thomas Tuchel, he has seen the returning Ilkay Gundogan and young starlet Julian Weigl usurp him as the preferred platform at the base of midfield.

Time to go? Bender is into his seventh year at the Westfalenstadion (Photo: Lars Baron)

The rest of the time, he's been utilised at centre-half, covering for the likes of Hummels and increasingly Neven Subotic - in three of the last four games he's been at the heart of defence.

But he still sees himself as a midfielder and he’s now available at a somewhat reduced price - no longer as high as the £20million valuation Arsenal were quoted 18 months ago. His combative nature makes him appear a perfect fit for the Premier League, even if teams need to take his injury record into account.

Marvin Plattenhardt (Hertha BSC)

Position: Left-back

Age: 23

Long run: Plettenhardt has impressed during Hertha's renaissance (Photo: AFP/Getty)

Signed from Nurnberg for a bargain £500,000 in 2014, Marvin Plattenhardt originally arrived at Hertha BSC as backup for Nico Schulz, seen as a player of high potential and one for the future. Within six months, Plattenhardt had made the No.3 spot his own, pushing Schulz into a midfield role and eventually encouraging Die Berliners cash in on the younger man.

Hertha's decision to place their faith in the 23-year-old has paid dividends since. Hertha sit third and are challenging for a Champions League spot, their defence bettered only by Bayern, while they've scored more than both Bayer Leverkusen and Schalke.

Cross: Plattenhardt has three assists in the Bundesliga this term

Pai Dardai's side are organised, defensively sound and counter well; former German under-21 international Plattenhardt plays a key role in their ability to transition from back to front; always quick to bring the ball out into space, always willing to hit the byline and always looking to be direct.

Blessed with plenty of pace, good technique and an excellent left foot, he's also very handy from set pieces. A very impressive 2015 saw Hertha extend his contract in the capital until 2020, however if the price is right, then they could well cash in on a man who is on the verge of senior international honours.